The Sheriff's Department had probed the Relativity Media exec for landing on an LASD helipad during the Christopher Dorner manhunt.

The L.A. County District Attorney's Office has dropped a criminal investigation into whether mogul Ryan Kavanaugh broke the law bylanding his helicopter on a Sheriff's Department helipad in February, during the Christopher Dorner manhunt.

In evaluating the Feb 7. incident, when the Relativity Media CEO landed at LASD's Biscauluz Center helipad, the DA's office determined that "there is insufficient evidence to prove that Kavanaugh landed his helicopter without permission or that he operated it in a careless or reckless manner."

At the time, the LAPD was organizing a search forDorner, who had embarked on a killing spree.

The 38-year-old exec stated, according to DA documents dated July 29, that he landed at the helipad before a meeting with Paul Tanaka, the former second-in-command to Sheriff Lee Baca. Kavanaugh stated that Tanaka sent him a text message giving approval to land on the helipad. The mogul is said to be supporting Tanaka as a possible challenger to Baca in 2014, when the sheriff is up for re-election.

The office first declined to file charges April 18 but then reviewed the allegations a second time. Kavanaugh's attorney, Blair Berk, sent a letter to the DA's office July 15 asking that charges not be filed.

"We're pleased that the District Attorney's office reached the obvious conclusion for the second time," said David Shane, a spokesperson for Kavanaugh and Relativity Media, in a statement to The Hollywood Reporter. "It's shameful that the sheriff wasted precious taxpayer time and money to fuel his political agenda."

A source close to the mogul previously toldTHR that, as of last weekend, Kavanaugh had not been notified of this particular investigation and described the probe as "political payback" for his support of Tanaka.

Sheriff Baca spokesman Steve Whitmore confirmed that the investigation was closed. "We respect their decision, and this matter is now closed for the L.A. County Sheriff's Department, and it was never politically motivated," he told THR.

Kavanaugh is a volunteer for the Sheriff Department's tactical aviation Aero Bureau. The executive has received complaints for his helicopter commutes from Malibu to Los Angeles in the past.